US1643483A

US1643483A - Turbine-pump governor

Info

Publication number: US1643483A
Application number: US636778A
Authority: US
Inventors: Joseph M Barrett
Original assignee: S C REGULATOR Manufacturing Co
Current assignee: S C REGULATOR Manufacturing Co; S-C REGULATOR MANUFACTURING Co
Priority date: 1923-05-04
Filing date: 1923-05-04
Publication date: 1927-09-27
Anticipated expiration: 1944-09-27

Description

Sept. 27 1927.

' 1,643,483 J. M. BARRETT TURBINE PUMP GOVERNOR Filed May 4, 1923 2 Sheets-Sheet l JIXZSZELITIOR ATTY;

2 1 Sept 927 J. M. BARRETT TURBINE PUMP GOVERNOR Filed May 4, 1923 2 Sheets-Sheet 2 Exam 1 02a $9 06 2L mm; M401 1 (YZ'ZZ OZZLVEi S Patented Sept. 27, 1927.

PATENT OFFiC-E.

JOSEPH M. BARBETT, OF FOSTORIA, OHIO, ASSIGNOB TO THE S-O REGULATOR MANU- FACTURING COMPANY, OF FOSTORIA, OHIO, A CORPORATION 01 OHIO.

TURBINE-PUMP GOVERNOR.

Application filed May 4, 1923. Serial No. 636,778.

This invention is concerned primarily with pump governors adapted to operate valves to vary the effective steam line to the pump. Recent developments in prime movers, such as are used in central power station plants, have brought about the use of steam under high pressures and high temperatures, the prevailing practice being to generate the steam in the boilers under from 350 to 500 pounds pressure and at temperatures ranging from 500 to 750 degrees Fahrenheit, superheat. The solution 7 of the primary problem of generating power economically by such practices has introduced many other problems in the development and design of auxiliary machinery used in the power plant and one of the most difficult problems has been to develop a pump governor for turbine-driven'hydraulic pumps, such as are used for feeding water to the boilers, against high pressures. It is desirable that the feed pump pressures be maintained at a constant excess over the'boiler pressures, this excess pressure being dependent upon the relative g5 disposition of the boiler and the feed water pump. It is very importantthat this difference in the pressures be maintained constant regardless of momentary fluctuations in the steam pressure, or regardless of the Varying demands on the pump.

The general object of the present invention, therefore, is the provision of a turbinedriven pump governor, which will respond instantly in its regulatory action upon-the feed water pressure to variations in the steam turbine pressure and effect this regulation in a smooth and gradual manner, yet

with sufficient rapidity to respond to the extremely sensitive action of a turbine throttle.

A further object bfmy invention is the provision of a pump governor, adaptable to the maintenance of a constant difference or excess pressure in, the feed water line over the steam turbine line, and whichembodies a-frictionless mechanism adapted to function in a sensitive manner under extremely high ten'iperatures and pressures; An additional object of the present invention is the provision of an extremely sensitive turbine pump governor which involves simple construction characteristics thereby securing a continuity of service when operating under high pressures and temperatures, the construction of the mechanism being such that no searching or so called hunting effect is present.

Other objects of my invention will be hereinafter set forth in the following description which refers to the accompanying drawings, illustrating a preferred embodiment thereof. The essential characteristics are summarized in the claims. I

In the drawing, Fig. 1 is a side elevation of my device; Fig. 2 is a cross sectional elevation thereof and is taken along the line 22 of Fig. 1; Fig. 3 is a cross sectional view taken substantially along the line 33 of Flg. 2; Fig. 4 is a cross sectional view taken substantially along the line 4-4 of Fig. 2; and Fig. 5 is a cross sectional view taken along the line 5-5 of Fig. 2.

My invention contemplates the use of a governor valve mechanism wherein the respective parts of the mechanism. are completely encased and are arranged in a coacting manner to prevent friction caused from rubbing of the respective parts. Such a mechanism involves the use of. a pressure diaphragm acted upon one side by the feed water pressure and on the opposite side bythe steam pressure of the boiler line, and a second diaphragm exposed to the steam pressure on one side and to atmospheric pressure on the other side, and connected to the first diaphragm by fulcrum levers whereby a pressure on the steam side of the first-named diaphragm may be exerted thereupon, which may always be in excess of the pressure on the hydraulic side of the diaphragm. I

thereby obtain a governor mechanism which does' not involve the use of springs or weights to counterbalance'the governor.

In Fig. 1, I show such a governor mechanism which comprises a valve body member 10, having a dividing wall 11, affording support for

valve members

12 and 13 which coact with valve closure members 14 'and' 15 respectively. The latter members are mounted upon theupper end of a floating stem 17, which has the lower end thereof connected to a diaphragm 18, through a fulcrum yoke 20 and pin 54:. The valve stem 17 is disposed within an exteriorly ribbed casing member 22, having an upper flanged end 23 thereof secured in clamped relation to a flanged branch 24 of the valve body member 10. The lower end of the casing member 22 is flared, as indicated at 25, to provide a diaphragm chamber, and terminates in a flange 26 which is in clamped relation with the perimeter of the diaphragm 18. A. bot-- tom closure member 28 is secured in clamped relation with the flange 26 of the casing member 22 and comprises the hydraulic pressure side of the governor. A hydraulic line 29 leading from the boiler feed water line of the pump serves to connect the interior of the member 28 to the boiler (not shown).

Attached to a branch 31 .of the casing member 22, and which is formed adjacent the lower end thereof, is a fulcrum and lever housing or casing member 32, which is also a support for a second diaphragm casing member 33. The

casing members

32 and 33 have the interiors thereof in communication with the interior of the casing member 22 through an opening 34. A second diaphragm 35, having the bottom side thereof exposed to the interior of the casing member 33 and the upper .side thereof exposed to the atmosphere, is maintained in clamped relation to the casing member 33 by a protecting cap member 37, suitably apertured, as indicated at 38, whereby the interior of this cap member is under atmospheric pressure.

By mechanically connecting the diaphragm 35 to the diaphragm 18 by means which-is entirely disposed within the

casing members

22, 32 and 33, and under the same pressure which prevails in the steam line,

it is possible to obtain an excess pressure upon the steam side of the diaphragm 18 opposing the counter-balancing hydraulic pressure which is exerted upon the under side thereof and within the member 28. This connecting means may comprise lever members pivotally mounted upon hardened knife-edge fulcrums, one of the-fulcrums being adjustable from the exterior of the device whereby the desired excess pressure may be readily and accurately obtained within the practical range of excess pressure adjustments of the governor mechanism.

. As shown in Fig. 2. this mechanism embodies a lever member 39, having one end thereof acting upon a knife-edged fulcrum member 40 pivotally secured to the yoke member 20 by a screw member 40 while the other end thereof extends between the arms of a fork member 41, the latter member rigidly carrying a fulcrum blade 42, which engages the end of the lever member 39 at the apex of a V-opening formed therein. The fork member 41 is connected to the diaphragm 35 through a rod member 43, which engages diaphragm clamping menr bers 44 and 45, disposed on the inner and outer sides'of the diaphragm respectively. I obtain adjustment of the excess pressure exerted upon the lower diaphragm by the upper diaphragm by adjusting an intermediate pivot for the lever 39. Disposed intermediate the ends of the lever member 39 therefore, and in slidable engagement therewith is an adjustable fulcrum bearing member 46, which engages the lever member 39 along a flat top surface thereof. This member is in the nature of a shoe mounted upon a yoke member 47, which isiin slidable engagement with the side walls of the casing member 32. As illustrated in Fig. 5, the yoke member 47 is adjustably supported upon the inner end of a screw member 50, which extends through the arms of the fork member 41, and outwardly through a pacle ing joint 51, whereby the outer end thereof is disposed exteriorly of the device. To further carry out the anti-friction design of this device, I also provide a fulcrum bearing member 52 upon the valve stem yoke 20, which engages a lower knife edge formed on the fulcrum block 40. This bearing block 52 may be secured to the yoke member by any suitable means, such as a pin member 53. The pin member 54 which connects the yoke member-2O to the diaphragm is rigidly fixed to flanged

diaphragm clamping members

55 and 56, disposed upon the upper and lower sides of the diaphragm, respectively.

In the particular arrangement disclosed, the intermediate fulcrum for the lever 39, is adjusted to a position whereby the lever arms have a two to one lever ratio, that is,

when the hydraulic pressure has a tendency to raise the diaphragm 18 a certain distance upwardly, the hydraulic pressure has a tendency to move the diaphragm 35. It will thus be seen that the area of the diaphragm 35 bears a definite relation to the area of. the diaphragm 18 and the major division of the pressure governing characterictics of this device is determined by calculating the respectiveareas, as will hereinafter be set forth, and the predetermined pressure regulating characteristics may be varied substantially twenty percent above or below the desired excess pressure by adjusting the pivotblock 46 in either direction from its two to one lever arm ratio position; I find the convenient formula for determining the proper In practice, a standard area is determined for the diaphragm 18, which therefore be-. comes constant, and the area ofthe diaphragm 35 is varied depending upon the, particular excess pressure and immediate ranges thereof which may be desired.

I find that a governor made in accordance the diaphragm. I accordingly extend the hydraulic pressure casing members 28 downwardly a suificient distance, whereby the lower part thereof may comprise a cylinder adaptable for the reception of a dashpot 60, which may have an upwardly extending stem 61 secured to a diaphragm clamping member 56, by a coupling member 62.

The action of this dashpot may be regulated by permitting hydraulic pressure to be exerted upon the upperv and lower ends thereof, and I therefore, provide a passageway 63 formed in the casing member 28, which establishes communication between the hydraulic pressure chamber and lower end of the piston member 60. This passageway may be regulated by a valve member 63 which may have the inner end thereof adjusted relative to a small opening 64, whereby the area of the passageway may be varied. This valve member (33 is 1n threaded engagement with the casing member 28 and locked in adiusted position by any suitable means, such as a lock nut member 65. A cap member 66 may be provided to completely shield the needle valve member 63 and the locking member 65. l The operation of the mechanism is as folows:'

When steam v is admitted to 'the turbine line, the

casing members

22, 32, and- 33,-

rapidly fill withcojndensate until the casing member 22 has a water line which is substantially at the height of the radiating rib 22 which is the third rib from the valve body 24. The radiating ribs formed on the casing member 22, serve to maintain the temperature ,of this eondensatelow relatively to the temperature of the turbine steam line, and Ills the mechanism disposed within the respective casing is thereby protected from the excessive superheat of this steam. The

condensate is maintained at the level referred to by reason of a liberal passageway formed in a bushing member 70. which does not contract with the piston stem 17, but acts merely as a step in limiting the downward or opening ll'lOVBll'lOlltS of the

valve members

14 and 15. The

diaphragms

18 and 35, are therefore under a pressure which is equal to the steam pressure in the line but are completely insulated from the steam pressure.

The diaphragm 18 is deflected downwardly by this pressure and the diaphragm 35 is deflected upwardly thereby. The upward movement of the latter, acts upon one end of the lever member 39 and causes it to exert an additional or excess pressure upon the diaphragm 18, through the fulcrum blade 40 and yoke member 20, secured to the

valve members

14 and 15 and these valve members .are thus drawn downwardly out of contact with their respective cooperating valve seat members 12 and '13. This condition prevails until the hydraulic pressure in the'feed water line connected to the turbine driven pump, 7

is equal to the steam pressure in the steam line leading to the turbine, pump, plus the additional or excess pressure exerted upon the diaphragm 18 by reason of the upward movement of the diaphragm 35, and the action of the interconnecting mechanism disposed therebetween.

If it is desired to decrease this excess pressure within reasonable limits, the screw member 15 may be adjusted to cause the fulcrum block 46 to be shifted towards the valve stem casing 22, and the action of the lever upon the diaphragm 18 is decreased. If it is desired to increase the pressure, the fulcrum block 46 may be adjusted outwardly towards the outer end of the screw member 50 and the action upon the diaphragm 18 is increased.

My governor mechanism does not involve any springs, weights or sliding members and thereby avoids the introduction of such diificulties as wearing and sticking of the moving parts, and variations in the action of such members due to friction. The means for connecting the diaphragms to the valve members is entirely free of any sliding contact and there is an absenceof packing glands or joints on all of the moving elements of my mechanism. Furthermore, the

nature of the mechanism is such that the various pivoting means embodied therein,

may comprise hardened knife-edge fulcrum blocks which are protected'from the dete-.

riorating effect of the superheated steam by reason of, the fact that my entire counterbalancing mechanism is insulated from the steam by a condensate bath.

Some distinct advantages are to be found in the use of such a device in that its instantaneous response to variations in the steam line leading to the turbine pump efl'ects a regulation in the feed water pressure to such an extent that pressure charts taken simultaneously of the steam linevpressure and the feed water line or hydraulic pump pressure discloses two curves which are identical in their smallest details of variation, the curves being spaced apart a distance corresponding to the desired constant excess pressure to which the mechanism has been set. The use of my device eliminates poundingor water hammer in the feed water line. and prevents an over-feeding or underfeeding of the boilers when unusual demands are made upon the steam line, and is extraordinarily instrumental in furthering the obtaining of proper heat balances in central power station operation.

What I claim is 1. In a pump governor, the combination of a valve, a valve member adapted to control the flow of. steam to a turbine, a diaphragm exposed on one side to the pressure of said steam and adapted to be exposed on the'other side to the hydraulic pressure of the pump, a second diaphragm exposed to said pressure on-one side and to atmospheric pressure on its opposite side, and means connecting the two diaphragms in supplemental and coacting re ation to said valve member whereby the valve member may be maintained open against a hydraulic pressure which is in excess of the steam pressure exerted on the diaphragms.

2. In apump governor, the combination of a valve member, a diaphragm. means connecting the diaphragm to the valve member, a second diaphragm and motion varying means connecting the second diaphragm to the first diaphragm, whereby the action of one diaphragm-may be in a direction opposite to the action of the other diaphragm and said diaphragm connecting means may be thereby operated to exert different pressures in a common direction with the first named diaphragm.

3. In a valve, the combination of closure means therefor, a diaphragm exposed to the pressure in the valve. a second diaphragm arranged to be exposed to said pressure, one of said diaphragms being adapted to be ex-. posed to other than atmospheric pressure, the other of said diaphragms being adapted to be exposed to atmospheric pressure, means connecting the first named diaphragm to said valve closure means, and other means connecting the second diaphragm to the first diaphragm in adjustable supplementary relationship.

'4'. In a pump governor, the combination of avalve body member disposed in a steam line. a valve member disposed therein adapted to close the steam passageway extending through the, valve bodv member, a casing secured to and depending from said valve body member and communicating with the steam line. a diaphragm secured to the lower end thereof and exposed to steam pressure on one side and water pump pressure on the other side, a movable means for connecting the valve member to the diaphragm, said movable means being suspended within said casing independently of the walls of the valve body member and said casing, a second diaphragm exposed to steam pressure and associated with the first diaphragm, connecting means between the diaphragms, said means being completely enclosed in the casing, and means within the casing for varying the action of the second named diaphragm upon the first diaphragm whereby the forces due to steam pressure are integrated to oppose the force due to water pump pressure.

'5. In a pump governor, the combination of a valve body member adapted to be connected in a steam line leading to the turbine of the pump, a valve member for interrupting a passageway extending through the valvebody member, a casing member adapted to retain a hydrostatic column, a pair of diaphragms and pressure varying means disposed therebetween, a fulcrum connection between the diaphragms and associated with said pressure varying means. and a second casing member secured to the bottom of said first casing member whereby hydraulic pressure may be exerted upon the under side of the diaphragm closing the bottom of said first named casing member, and means disposed below said diaphragm and acting thereupon to retard vibratory movements thereof. i

6. In a pump governor, the combination of a valve body member adapted to be connected in a steam line leading to the turbine of a pump, a valve member for closing a passageway extending through the valve body member, a casing adapted to retain condensate, a diaphragm exposed to the condensate, a second diaphragm associated with the first diaphragm and arranged "to respond and to receive pressure on the other side from the steam line in which said valve member is disposed, and excess pressure means actingupon the steam side of the diaphragm including a second diaphragm having an area greater than the exposed area of the first named diaphragm whereby the excess pressure plus-the steam pressure may equal the water pressure. i

8. In a pump governor of the character described, the combination of a valve body member having a low and a high pressure. chamber, a valve member closing communica tion between the respectivechambers. a diaphragm exposed to high fluid pressure on oneside, means connecting the valve 'mem ber and the diaphragm, a second diaphragm adapted to deflect when the first named dia phragm deflects in response to another fluid pressure common to both diaphragms, and

phragm deflects.

phragm, said means including a pivotallymounted member, and a mounting therefor,-

whereby adjustment of the mounting will vary the excess pressure exertedupon .the first named diaphragm when the second dia- 9. ln a'valve, the combination of a dia phragm operated valve closure member, a diaphragm therefor exposed on opposite sides to different fluid'pressures, a second diaphragm having an exposed area greater than the first diaphragm and exposed to the lesser of the fluid pressures exerted upon the first diaphragm, and means connecting the diaphragms whereby a deflecting movement of the second diaphragm will exert an excess .pressureupon the first named diaphragm equall-to the difference in fluid pressure thereon.

10. In a "pump governor of the character described, the combination of a valve body member having a high and a low pressure chamber, a valve member closing communication between the respective chambers, a casing secured to the valve body member with the interior thereof in communication with the high pressure side of the valve body member, a diaphragm closing an opening in said casing, a second diaphragm closing a branch opening extending from said casing, a valve stem connecting the first named diaphragm with said valve member, said valve stem being movable independently of the walls of the casing, a fulcrum lever disposed within said branch opening and connected with one end of said valve'stem and at the other end to said diaphragm, and adjustable fulcrum mounting therefor, and means extending from the exterior to the interior of the casing for varying the position of said fulcrum mounting.

11. in a pump governor of the character described, the combination of a valve body member having a high and a low pressure chamber, a valve member closing communication between the respective chambers, a easing secured to the valve body member with the interior thereof in communication with the high pressure side of the valve body member, a diaphragm closing the bottom of said casing member, a second diaphragm closing the opening of a branch extending from said casing, an interiorly disposed means connecting the diaphragms in supplemental relation with said valve member, ineluding a fulcrum lever disposed within said branch, an adjustable fulcrum mounting therefor, and means for varying the position of said fulcrum mounting.

12. In a steam pump governor of the character described, the combination of a valve body member, a valve controlled passageway extending thereto, a casing member secured to the valve body member with the interior thereof in communication with said passageway, said casing having openings closed by a pair of diaphragms, whereby pressure within the casing will deflect the diaphragms outwardly, means connecting the two diaphragms wherebyoutward movement of one diaphragm will cause additional pressure to be exerted in the same direction with the other diaphragm, said means including a fulcrum lever and a slidably mounted fulcrum block therefor, and means extending from the exterior to the interior of the cas ing for adjusting the position of said fulcrum block. a

13. In a valve, the combination of a valve body member, a' valve member controlling a passageway extending therethrough, a casing member secured to the valve body member with the interior thereof in communication with said passageway, said casing having openings closed by diaphragms, whereby pressure within the casing will deflect the diaphragms outwardly, and means connecting the two diaphragms whereby outward movement of one diaphragm will cause additional pressure to be exerted upon another diaphragm, said means including a fulcrum lever and a slidably mounted fulcrum block therefor, and means extending from the exterior to the interior of the casing for adjusting the division of said fulcrum block.

1 4. Ina pump governor, the combination of a valve, a valve member adapted to con trol the flow of steam toa turbine, a movable member exposed on one side to the DIGS- sure of said steam and adapted to b exposed on the other side to the hydraulic pressure of the pump, a second movable member exposed to said pressure on one side and to atmospheric pressure onits opposite side and means connecting the two movable members to said valve member whereby the valve member, may be maintained open against a hydraulic pressure which is in. excess of the steam pressure exerted on the movable member.

15. In a valve, the combinationof closure means therefor, a movable member exposed to the 'pressure in the valve a second movable member arranged to be exposed to said pressure, one-of said movable members being adapted to be exposed to other than atmospheric pressure, the other of said members being adapted to being exposed to atmospheric pressure, means including a beam supported on points to eliminate friction for connecting the first named movable member to said valve closure means, and other means connecting the second movable member to the first movable member.

16. In a steam pump governor, the com bination of a diaphragm operated valve member, an operating diaphragm therefor, whereby a deflecting movement of the second a second dlaphragm arranged to deflect undlaphragm W111 exert a variable excess presder a pressure which deflects the first named esure upon the first nameddiaphragm. 10 dlaphragln, means lncludmg a member sup- In testnnony whereof, I hereunto afl ix my ported on bearings, one of said bearings besignature. ing capable of manual adjustment along said member, for connecting the diaphragms JOSEPH M. BARRETT.